From bd8b639add3403c7a5dfae6993a6250b52358c60 Mon Sep 17 00:00:00 2001 From: Alasdair G Kergon Date: Thu, 31 Jan 2013 14:23:36 +0000 Subject: [PATCH] dm: fix write same requests counting When processing write same requests, fix dm to send the configured number of WRITE SAME requests to the target rather than the number of discards, which is not always the same. Device-mapper WRITE SAME support was introduced by commit 53e4b0875f687402f8ada987da93423cf3ce01d6 ("dm: add WRITE SAME support"). Signed-off-by: Alasdair G Kergon Acked-by: Mike Snitzer --- drivers/md/dm.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/drivers/md/dm.c b/drivers/md/dm.c index c72e4d5a96178..314a0e2faf79d 100644 --- a/drivers/md/dm.c +++ b/drivers/md/dm.c @@ -1188,6 +1188,7 @@ static int __clone_and_map_changing_extent_only(struct clone_info *ci, { struct dm_target *ti; sector_t len; + unsigned num_requests; do { ti = dm_table_find_target(ci->map, ci->sector); @@ -1200,7 +1201,8 @@ static int __clone_and_map_changing_extent_only(struct clone_info *ci, * reconfiguration might also have changed that since the * check was performed. */ - if (!get_num_requests || !get_num_requests(ti)) + num_requests = get_num_requests ? get_num_requests(ti) : 0; + if (!num_requests) return -EOPNOTSUPP; if (is_split_required && !is_split_required(ti)) @@ -1208,7 +1210,7 @@ static int __clone_and_map_changing_extent_only(struct clone_info *ci, else len = min(ci->sector_count, max_io_len(ci->sector, ti)); - __issue_target_requests(ci, ti, ti->num_discard_requests, len); + __issue_target_requests(ci, ti, num_requests, len); ci->sector += len; } while (ci->sector_count -= len); -- 2.39.5